1. Field of the Invention
The present invention relates to portable building structures, and more particularly to a utility shed structure that can be easily assembled and knocked down without the use of special tools.
2. Description of the Prior Art
In certain industries, such as the construction industry in particular, there is always the need for providing temporary shelter, security, and storage for tools, equipment, machinery, and supplies. Trailer-type buildings are typically too expensive and complex for these purposes. Pre-fabricated sheds are more suited for such temporary storage purposes, and a variety of them are commercially available; however, these pre-built structures do not lend themselves to transportation from one temporary site to another since they require special handling and transportation by a truck or flatbed trailer, and repeated moving can adversely affect the structural stability of such sheds. Furthermore, such commonly available utility sheds and the like are designed to be assembled permanently and permanently installed at a business, commercial or residential location, and cannot be conveniently disassembled for transport and reassembled. Such pre-built sheds can also be relatively expensive.
In an attempt to address these needs, the prior art reveals a few developments of portable building structures that are designed to be disassembled and re-erected as required. See U.S. Pat. Nos. 117,721, 2,231,065, and 4,676,039 for examples. While these patented systems have their particular advantages, they unfortunately also have their limitations and shortcomings. The disclosure of U.S. Pat. No. 117,721 discloses a system that calls for peculiar shaped bolts and elongate vertical weather strips for forming corners for wood plank side wall panels, and several such bolts per corner must be installed using a special hand tool. Such a design would not appear to lend itself to modern materials and structures, requires too much labor, and does not appear to have the durability required for repeated use. U.S. Pat. No. 2,231,065 shows an easy-assembled sheet metal building that uses interconnectable side wall and roof sections. Vertical edges of the panels are prefolded to form channels and flanges that can be slidably connected to each other to form corner joints. Although such a building can be assembled without special tools, it appears that an appreciable amount of labor will nevertheless be required for the longitudinal sliding movement required for each joint and the deleterious effects of corrosion and distortion of the sheet metal over time make such developments unsuitable for repeated assembly and disassembly for which use it is clearly not intended. U.S. Pat. No. 4,676,039 shows a portable building that is designed to be easily assembled as well as knocked down. It relies on specially shaped vertical edges on its side panels and a separate specially shaped corner post to interconnect one side panel to another to form a building corner. Among the limitations of such design it is noted that the extruded components are somewhat complex, and unfortunately a considerable amount of rotation of each panel is required to connect a panel to a corner post, which can be an inconvenient and time consuming maneuver.